This super wide-angle zoom lens allows you to take wide photographs even with digital SLR cameras which have a screen size smaller than 35mm, covering the range from a super wide-angle 17mm to a standard 40mm. Three aspherical lens elements which come in two types deliver both a wide zoom range and high image quality, while the super UD lens elements provide excellent correction of the magnification-type chromatic aberration. Innovations such as a lens coating optimized for digital photography help minimize flare and ghosts, which often occur with digital cameras. The circular aperture diaphragm which brings out a nuanced blur and the achievement of a closest focusing distance of 0.28m over the whole range of the zoom, not only help you in composition, but the quiet, high-speed autofocus and the outstanding dust-proof*1 construction make this lens extremely mobile. The front filter mount does not rotate during focusing, so there is no problem when using circular PL filters or other filters, and in combination with the EF70-200mm f/4L IS USM you can get the right shot almost anywhere you go.